https://phys.org/news/2018-06-team-micro-embossing-equipment-precision-optical.html

The research team led by Professor LEE Wing Bun and Dr. LI Lihua from PolyU's Department of Industrial and Systems Engineering has adopted a novel molding design with graphene-like coating and self-developed heating technology to produce the micro-embossing equipment to produce micron-level microstructural optical components in glass. Compared to conventional bulky infrared heating devices with high energy consumption, the novel technology is more environmentally friendly and cost effective.

The use of a graphene-like coating can heat up the optical glass precisely and quickly with low energy consumption, while reducing thermal expansion and deformation of the mold. The control and monitoring software can also provide instant online readings of the temperature to allow fine-tuning and adjustment of the process parameters, and thus shorten the cycle time. Such novel features enable saving electric power by up to 60 times, compared to conventional infrared machines, and cutting the manufacturing cost by two-thirds. Being an electrically conductive material with high wear characteristics, graphene also enables smooth stripping of the glass workpiece from the mold after the embossing process. Furthermore, micron-scale pattern can be replicated on the glass substrate.